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Chemical Modifications of Biopolymers by Quinones and Quinone Methides
Angewandte Chemie International Edition in English, 1989AbstractMany quinones and their precursors, which are transformed oxidatively into quinones and/or quinone methides, are important natural products. As secondary metabolites, they frequently possess antibiotic and cytotoxic activities, in addition to acting sometimes as pathogens. Several plants and animals, especially insects, use quinonoid substances
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Quinones as antimycobacterial agents
Bioorganic & Medicinal Chemistry, 2004Mycobacterium tuberculosis is a serious worldwide health threat, killing almost 3 million people per year. Other mycobacterial species, especially Mycobacterium avium, are emerging pathogens in the immunocompromised population, most notably AIDS patients. These nontuberculous mycobacteria (NTM) are ubiquitous in the environment, and naturally resistant
Violeta Chavez +6 more
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Structure−Activity Study on the Quinone/Quinone Methide Chemistry of Flavonoids
Chemical Research in Toxicology, 2001A structure-activity study on the quinone/quinone methide chemistry of a series of 3',4'-dihydroxyflavonoids was performed. Using the glutathione trapping method followed by HPLC, (1)H NMR, MALDI-TOF, and LC/MS analysis to identify the glutathionyl adducts, the chemical behavior of the quinones/quinone methides of the different flavonoids could be ...
Awad, H.M. +5 more
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Quinones and quinone-methides—I
Tetrahedron, 1977Abstract Silver oxide or 2,3-dichloro-5,6-dicyanobenzoquinone oxidation of 2-cinnamyl-4,5-methylenedioxyphenol yields a crystalline ortho-quinone methide, which undergoes thermal or acid-catalysed cyclization to 6,7-methylene-dioxyflav-3-ene. Oxidation of 2-(4-methoxybenzyl)-4,5-methylenedioxyphenol yields a crystalline ortho-quinone methide which ...
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Photochemical additions of aldehydes to quinones, quinone imines and quinone oximes
1968Klinger [1,2] found that 9,10-phenanthrenequinone reacted with aliphatic and aromatic saturated and unsaturated aldehydes e.g. acetaldehyde, benzaldehyde, and cinnamaldehyde under the influence of light. The photo-adducts 1 may be cleaved hydrolytically to give 9,10-phenanthrenediol and RCOOH; it is possible thus to convert aldehydes to the ...
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Function of Quinones in Photosynthesis
1967Publisher Summary The quinones that are commonly found localized in chloroplasts are of three major types: the plastoquinones, tocopherylquinones, and vitamin K. In each of these groups, there is more than one type present. Plastoquinone A has a side chain with nine monounsaturated isopentenyl (isoprenoid) units.
M.D. Henninger, Frederick L. Crane
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The Cofactor Pyrroloquinoline Quinone
Annual Review of Nutrition, 1990Article de synthese sur un cofacteur: la pyrroloquinoleine quinone. Etude de ses proprietes; caracteristiques, formes moleculaires, stabilite. Identification et analyse quantitative des formes libres, derivees et liees par liaison covalente. Distribution chez les procaryotes, les eucaryotes, les aliments et les boissons.
R. A. van der Meer +2 more
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Journal of the Chemical Society, Perkin Transactions 1, 1999
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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Acetylenic derivatives of quinones
Russian Chemical Reviews, 2004AbstractFor Abstract see ChemInform Abstract in Full Text.
Lidiya G. Fedenok +2 more
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1990
The concept that the long-chain quinones in energy-transducing membranes (Fig. 5.1 A and B) act as mobile carriers of electrons and protons is partly based on the high concentration of quinone in all energy-transducing membranes (Table 5.1). This quinone can be readily extracted with organic solvent.
David B. Knaff, William A. Cramer
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The concept that the long-chain quinones in energy-transducing membranes (Fig. 5.1 A and B) act as mobile carriers of electrons and protons is partly based on the high concentration of quinone in all energy-transducing membranes (Table 5.1). This quinone can be readily extracted with organic solvent.
David B. Knaff, William A. Cramer
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